Wheeled base for office machines



April 30, 1957 w. LUBBE 2,790,649

WHEELED BASE FOR OFFICE MACHINES Filed Dec. 15, 1954 United StatesPatent M WHEELED BASE FOR OFFICE MACHINES Walter Liibbe, Wilhelmshaven,Germany, assignor t0 Olympia Werke Aktiengesellschaft, Wilhelmshaven,Germany Application February 15, 1954, Serial No. 410,104

2 Claims. (Cl. 280--47.13)

In order to facilitate the displacement of oflice machines, for examplecomputing machines, over a table surface or the like such machines areusually provided with supporting rollers consisting of elastic material,arranged under a base plate of the machine and adjacent the cornersthereof. The base plate is secured to the machine housing at the lowerside thereof. The elastic supporting rollers at the rear end of themachine are mounted on a shaft which is supported in the legs of aLl-shaped holder member consisting of pressed sheet metal. Displacementof the machine over the table surface is accomplished with the frontpart of the machine slightly raised, the supporting rollers rolling onthe table surface.

It is an object of the invention to divide the supporting rollers intheir holders with regard to their length in such a manner that theypermit a compensating rotation of the parts on their shafts in theholders, i. e. that the different lengths of travel of the supportingrollers which result when the machine is displaced along a curved pathare compensated for by a difierential action.

In the novel holder construction according to the invention thesupporting rollers are substantially arranged in such a manner that atleast two rollers are rotatably supported on the shaft of each holder,thus each of the rollers being freely and independently rotatable on thecommon shaft. The individual rollers are conveniently separated fromeach other by spacer means which may consist of a spacer ring arrangedon the shaft.

If the rollers are made very narrow or with little elasticity thearrangement of the Web parts of the U-shaped roller holders in recessesof the above mentioned base plate may, according to another feature ofthe invention, be made in such a manner that each holder web isnonrotatably located in the corresponding recess of the base plate bymeans of a locating pin engaging a bore in the base plate; or thislocation may be accomplished by the provision of corresponding abutmentshoulders on the holder web and the recess.

The marginal zone around the hole, provided in the web portion of theholders for the passage of the mounting bolt, may be bent outwardly inthe direction of the legs of the U-shaped holder to form a conicalprojection, against the inner diameter of which abuts the conical headof the mounting bolt. Centering is thus accomplished independently ofthe adjustment of the hole to the bolt diameter which would otherwise benecessary simply by the abutment of the conical bolt head (countersunkhead screw) against the inner periphery of the bentout conicalprojection. In this case it is not required that the diameter of thehole be very accurate in relation to the bolt diameter. The bent-outconical portion also serves to stiifen the Web portion of the holder.These mounting means, together with the aforementioned locating pinsand/or abutment shoulders, constitute the means for effecting anon-rotatable connection of the holder with the base plate of themachine.

Further details of the invention will be apparent from 2,790,649Patented Apr. 30, 1957 the following description of an embodiment of thenovel holder construction for supporting rollers on an oifice orcomputing machine which are given by way of example only, and areillustrated in the accompanying drawing in which:

Fig. 1 is a side elevation of an oflice or computing machine showing thearrangement of the supporting rollers at the rear end of the base plateof the machine;

Fig. 2 is a perspective view of a holder construction withsupporting'rollers adapted for non-rotatable mounta;

Fig. 3 shows the component parts of the construction according to Fig.2, and also the mounting bolt with coni cal head used with this holderconstruction;

Fig. 4 shows a base plate of a machine with two holders for supportingrollers in perspective representation;

Fig. 5 is a plan view of a corner of a machine base plate with a recessfor the reception of a holder adapted to be non-rotatably secured bymeans of a locating pin and/ or abutment shoulders;

Fig. 6 is a sectional view taken along line VI-VI of Fig. 4 inconnection with part of a machine housing including the base plate.

The office or computing machine A generally indicated in Fig. 1 has atits rear end under the base plate 7 supporting rollers 1 of elasticmaterial which are supported in holders 2 of pressed-sheet metal. At'the front end the machine rests on rubber butters 2' in the usualmanner. As may be seen from Figs. 2, 3, 4, and 6, the holders 2 comprisea plane web portion 2a from which extend two legs 2b which are so bentthat they are situated opposite each other and form a U-shape togetherWith the web portion 2a. The legs 2b of the U comprise bores 20 adaptedto receive a shaft 3 which is located in axial direction in the legportions 2b of the U-shaped holder 2 by means of securing member 4. Innormal working position the shaft 3 is disposed in the holder 2 inparallel relation to the base plate 7 of the machine A. The narrowsupporting rollers 1 are provided with rigid bearing bushes 1'consisting of metal. On each shaft 3 there are mounted two supportingrollers 1 which are rotatable freely independently of each other. Theyare separated by spacer means in the form of a spacer ring 5 slippedover the shaft 3 so as to be freely rotatable thereon. The legs 2b ofthe U-shaped holder 2 projecting from the plane web portion 2a formabutment shoulders. Conveniently, the Web portion 2a between the legportions 2b is of circular shape over a substantial part of itscircumference. As may be clearly seen from Figs. 2, 3, and 6 themarginal zone around the hole for the conical-head mounting bolt 6(countersunk head bolt) is bent outwardly at 11 in a conical form, andin the direction of the legs 2b of the U. In the direction opposite tothe bent-out portion 11 extends a locating pin 12. The web portion 2a ofthe holder 2 fits into a recess 13 formed by drawing in the base plate 7secured to the machine housing 8 at the lower side thereof. Towards theedge of plate 7 the recess 13 terminates in two parallel abutmentshoulders 14 as may be seen from Fig. 5. These shoulders 14 cooperatewith the abutment shoulders, formed by the leg portions 2b of theU-shaped holder 2, so that the holder 2 is non-rotatably located whenits web portion 2a is in serted into the recess 13. In addition to orinstead of the abutment shoulders, a pin 12, engaging a bore 10 in thebase plate 7, may be provided to prevent rotation of the holder 2 withrespect to the base plate 7. The holder 2 is connected with the baseplate 7 and the machine housing 8 by means of a threaded bolt 6, anelastic cushioning ring 9 being interposed between the base plate 7 andthe machine housing 8, and the conical head on of the bolt 6 pressingagainst the free edge 11a of the conical bent-out portion 11. Thebent-out portion 11 not only serves to effect the previously describedcentering, but also stiflens and reinforces the web portionla of' theholder 2. The mounting bymeans of a countersunk head screw 6 in themanner described and illustrated does not only present theadvantage thatthe size-of the hole in the bent-out portion 11 is independent from thediameter of the threaded bolt 6 within certain limits, but is alsoadvantageous so far as exact centering of the base plate 7 is effectedby the conical part of the countersunk head screw 6 when screws ofdifferent sizes are used in different machinesor various machine partsand, for reasons of economy, are also to be employed for the presentpurpose. The arrangement of the supporting rollers 1 in each holder 2,at a distance fromand rotatable independently of each other, practicallyeliminates any rubbing action of the elastic rollers whenthelongitudinal axis of the machineA is directed tangentiallyto the pathof movement of the machine, because the rollers I assume differentrotational speeds, and are thus capable of compensating for thedifferent lengths of their travel.

I claim:

1. A holder construction for supporting rollers of clastic material ofan o'fiice' machine,:comprising in combination, a machine housing;.abase'plate secured to said housing at the lower side thereof; twoU-shaped holders of pressed sheet metal arranged at the rear end undersaid base plate, each of said holders havinga web portion; two threadedconical-head mounting bolts, each of said bolts mounting one of saidholders to said base plate; a shaft supported between the legs of eachof said holders and extending parallel to said base plate; two rollersbeing supported on said shaft of each of said holders so as to be freelyand independently rotatable thereon; spacer means, each arranged on saidcommon shaft between said two rollers adapted to hold said rollers inspaced relationship; two recesses drawn in said base plate and eachrecess adapted to receive said 'web portion of a corresponding one ofsaid holders; a hole provided in each of said web portions, the marginalzone around said hole being bent outwardly so as to form a conicalprojection, the conical part of each of said mounting bolts bearingagainst the edge of said projection.

2. The holder construction of claim 1, in which each of said recessesand each of said holders are provided with cooperating abutmentshoulders.

References Cited in the file of this patent UNITED STATES PATENTS150,132 Buckingham Apr. 28, 1874 785,601 Fischer Mar. 21, 1905 1,435,371Bartlett et al Nov. 14, 1922 2,068,160 Zeindler Jan. 19, 1937 2,311,928,Buehler Feb. 23, 1943 2,424,032 Henderson July 15, 1947 2,502,929 ClarkApr. 4, 1950 2,529,475 Anneren Nov. 14, 1950 2,575,968 McCallum et alNov. 20, 1951 FOREIGN PATENTS 220,780 Germany Apr. 8, 1910

